Published: May 31, 2011 4:00 AM

As the wheat gets closer to the flowering stage, and weather conditions remain wet, the question becomes, should we apply a fungicide to protect the wheat from head scab, and if so when?

According to Pierce Paul, plant pathologist at the Ohio Agricultural Research and Development Center, the only time a fungicide will protect the wheat from head scab is when it is applied while the wheat is in bloom. This will be happening soon in our area.

A wheat scab risk tool based on current weather conditions can be found online at www.wheatscab.psu.edu You can also keep up-to-date with the most recent releases from our state specialist by reading the C.O.R.N newsletter which is available through the Ag & Natural resource portion of our web page at www.wayne.osu.edu.

More advice from Peter Thomison and Robert Mullen. OSU Extension has developed a decision aid, "Estimated Yield and Profit by Planting Date -- Corn, Soybeans or Preventative Planting Crop Insurance" to assist producers in exploring the option of late planted corn, switching to soybeans, or accepting preventative plant payments. The aid is available at http://ohioagmanager.osu.edu. It allows farmers to enter their own production information to determine which choice might be best for their operation.

If switching to soybean and preventative plant crop insurance are not options, farmers need to reconsider their production practices and focus on those that will generate the greatest profits in a late planting production environment. What optimizes yield when corn is planted early doesn't always have the same effect when corn is planted in June. Some management adjustments will facilitate more rapid crop establishment and thereby limit yield losses associated with planting delays.

Consider the following management alternatives so that planting is not further delayed when favorable planting conditions occur and economic returns from various inputs are optimized --

Avoid high-end range N rates on corn following soybean. OSU research has shown that nitrogen rates can be decreased by 10 percent to 15 percent with minimal impact on productivity when corn is planted in early June.

Side-dress anhydrous N (or UAN liquid solutions) and apply a minimum of 30 lb/N broadcast or banded to stimulate early seedling growth. If you do not have the capability to apply N with your planter, a surface application of UAN as an herbicide carrier can be a way to carry your corn crop until sidedress N is applied.

Place starter applications of P and K in bands 2 inches to the side and 2 inches below the seed only if they are deficient in the soil.

No-till offers the best option for planting on time this year. Field seedbed preparation should be limited to leveling ruts that may have been left by the previous year's harvest -- disk or field cultivate very lightly to level. Most newer planters provide relatively good seed placement in "trashy" or crusted seedbeds.

Switch to an adapted short season hybrid. Although a full season hybrid may still have a yield advantage over shorter season hybrids planted in early June, it could have significantly higher grain moisture at maturity than earlier maturing hybrids if it dries down slowly. Moreover, recent evaluations indicate there are some 100-104 day relative maturity hybrids with excellent yield potential. However, performance data for such early hybrids is limited compared to late maturities. For more information on selecting corn hybrids for delayed planting, consult "Delayed Planting & Hybrid Maturity Decisions," a Purdue/Ohio State University Extension publication available online at: http://www.agry.purdue.edu/ext/pubs/AY-312-W.pdf (Consult "Table 4. Approximate "safe" relative hybrid maturities for delayed plantings throughout Ohio")

Reassess seeding rates. Soil temperatures are usually warmer in late planted fields, and as a result germination and emergence should be more rapid and uniform. So, as planting is delayed, seeding rates may be lowered (decreased to 3 percent to 5 percent higher than the desired harvest population) in anticipation of a higher percentage of seedlings emerging. Past university research indicates that optimal plant populations for early (mid to late April) and late planted (late May to early June) corn are similar. However, recent OSU studies suggest little benefit from increasing plant populations above 30,000 plants/acre in June. This lack of response to final stands over 30,000 plants/acre was associated with greater stalk lodging for hybrids planted during June compared to May.